Fiter design is the process of designing a filter.

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2answers
281 views

Is a high-passed signal the same as a signal minus a low-passed signal?

My question is, if I want to high-pass a signal, is it the same as low-passing a signal and subtracting it from the signal? Is it theoretically the same? Is it practically the same? I have searched ...
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0answers
17 views

How to use coefficients generated in c header file of fdatool in matlab?

I'm using the fdatool in matlab to design a high pass filter.I then generated the coefficients for direct form 1 structure.I exported it as a C header.The trouble is I have a vague idea as to how to ...
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0answers
11 views

2D IIR filter design (x-axis width proportional to y-axis)

I want to design a 2D IIR filter (that is, created line-by-line progressively). What is the best way to go about this? I would like the response to look something vaguely like this: The actual ...
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1answer
47 views

Multi-Stage digital FIR filter vs Single stage FIR filter. Which is better?

Can anyone provide an insight to select a filter structure out of multi-stage and single stage FIR filter?(it will be great help if references are also provided) Let's say I have to make 50 tap ...
2
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1answer
158 views

How to test the FIR filter in C++?

I am almost done with design and implementation of my first FIR filter using C++. Its a Sinc-Windowed FIR filter designed for a cut off frequency of 100 Hz with sampling rate of 500, with a filter ...
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0answers
3 views

Filter Span in SQRC filter in MATLAB

I'm simulating a Communication system but I'm not sure of how MATLAB defines "span" in command rcosdesign(beta,span,sps). Span is the the sample number? Or what else? Thanks in advance!
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1answer
44 views

Why should the cut off frequency and the transition bandwidth (BW) be expressed as a fraction of sampling rate?

I came across this confusion in Chapter 16,"Book - The Scientist and Engineers guide to DSP" and Topic is "Windowed Sinc-Filters". I am doing some calculations for designing the sinc filter and came ...
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1answer
30 views

Microphone Array null steering unexpected results after IFFT

I am writing an open source microphone array simulation program:SharpEar. When I give uniform weight to microphone array elements, the result in the angle is a sinc function as expected. There are 41 ...
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1answer
22 views

What is the relation of the transition band's width and the filter order for the FIR windowing method

When designing an FIR filter using the windowing method, how can one estimate the filter order ? It's obvious that the type of window and the transitions band's width has some effect on the order.
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1answer
26 views

Obtain transfer function from signal flow graph

I have a pretty complex signal flow graph with all the blocks and the branches completely describing an analog filter, in the Laplace complex variable s. The signal $X(s)$ is the input and $Y(s)$ is ...
1
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1answer
64 views

Question regarding filter implementation - Audio EQ Cookbook

Some of you may know the infamous Audio EQ Cookbook. You can take a look here. We tried to implement the functions there to achieve a implementation for a Lowpassfilter. However, when we try to ...
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2answers
36 views

How to select the center frequency and filter type for 5-band digital audio equalizer?

I have a small team project: use Matlab implement a Gui 5-band digital equalizer using FIR and IIR filters (2 cases) - The sample rate of all audio files is standard audio 44.1kHz. Coding is not my ...
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1answer
35 views

Apply FIR filters to Extract Stego from WAV data

I appreciate anyone that takes a moment to help me with this problem. I've been banging my head against the keyboard for a while, searching forums and DSP tutorials and I can't figure this problem ...
0
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3answers
91 views

In filter design, why isn't it possible to have a frequency response with phase 0?

A linear phase filter will cause a delay in the output signal of the filter. If I'm not mistaken, a filter with phase equal 0 would cause no delays in the output signal. Can someone explain me why ...
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0answers
27 views

Why Matlab fdatool designed butterworth filter and butter command's co-efficients are different

I met an great confusion. Using below command I have got co-efficents for a 300Hx cut-off high pass filter of order two. [z p k] = butter(2,(300/44100),'high') [sos,g] = zp2sos(z,p,k) Now ...
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0answers
28 views

Using bilinear method while filtering a signal - Matlab

i have to current signal in matlab: Fs = 8000; T = 1/Fs; N=512; t = (0:N-1)*T; ...
0
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1answer
36 views

Applying lowpass and highpass filters to an image in frequency domain in matlab

What i want is simply to apply low pass and highpass filters to an image in the frequency domain. Does matlab image processing toolbox have any commands for this?
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14 views

Higher dimensional Kaiser formula

Kaiser formula gives filter length for FIR filters. Is there a generalization of the formula to $2D, 3D, 4D, 5D,\dots$ FIR Filters?
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0answers
31 views

Basics of multidimensional filter design

Say you want to design a LP FIR filter with low pass cutoff $fc$, transition band $fc$ to $fs$ and ripple factor $dp$ at passband and $ds$ at stop band. If one divides the frequencies by pi, then ...
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2answers
55 views

FIR Filter length Upper Bound

Say I want to design a low pass filter with stop and pass band ripple constrained to $\epsilon$ and transition region $\delta$, what is the smallest FIR Filter length that suffices? Can you please ...
0
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1answer
50 views

Filter to speed up convergence of geometric series

I want to speed up convergence of geometric series $\ \ lim + c^n \ \ $ where $|c| < 1$ and $lim$ is not known. A basic low-pass filter, here Butterworth, is good for $-1 < c < 0$ but not $0 ...
0
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1answer
46 views

Calculating Savitsky-Golay filter coefficients - normalization

using the matrix equations found on Wikipedia i wrote some Python code to compute the Savitsky-Golay coefficients for m data-points, using a polynomial of degree k, here it is: ...
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2answers
91 views

FIR filter design with frequency sampling method - setting proper phase response for IDFT

I'd like to implement freuqency sampling method for linear phase FIR filter design using IDFT transform. My procedure goes like this : determine desired magnitude response value in frequency points ...
0
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1answer
54 views

how to make CIC compensation filter

I gotta wrap my head around to design CIC compensation filter I'm studying by referring these materials: Altera, "Understanding CIC compensation filters Hardware Efficient FIR Compensation Filter ...
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0answers
23 views

matlab : how to simulate behavior model 6th order DSM with 7th order CIC filter

I gotta wrap my head around to design 24bit DSM using matlab here is my design target. input magnitude : half scale (-6db) single tone input frequency : 96kHz OSR ...
0
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1answer
34 views

coded filter vs fdatool : inconsistency in the results for same parameters

I tried creating a filter in 2 different ways in Matlab and I obtain different results: one filter is stable, whereas the other one is unstable. Coded filter ...
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0answers
24 views

How to plot/graph frequency response of a continuous time comb filter?

How can I plot the frequency response of a comb filter, and how can I plot it so every octave from nyquist (normalized at x=0) is 1 unit on the graph? Sorry for the poorly phrased question, I am not ...
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2answers
44 views

Understanding Arrangement of second order sections

When splitting higher order recursive filters into more convenient 2nd order sections (biquads), in matlab, we usually use zp2sos to convert. In document, there's a ...
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1answer
89 views

digital butterworth filter design error

I am trying to design a digital butterworth filter for the given specifications.. code is posted below.. rp=3; rs=15; FS=1; wp=0.5*pi; ws=0.75*pi; pwp=2*FS*tan(wp/2); pws=2*FS*tan(ws/2); ...
2
votes
3answers
333 views

Audio EQ Cookbook without frequency warping

The famous http://www.musicdsp.org/files/Audio-EQ-Cookbook.txt offers a set of [real] biquad filter calculation formulas that generally work fine. However, when filter's frequency approaches Nyquist ...
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1answer
41 views

filter design for ECG

I would like to ask how to design a digital filter to remove $50$ Hz interference on an ECG signal. Do I need to use notch filter? Thanks.
3
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5answers
137 views

What's the Q factor of a digital filter's pole?

For the analog S-plane, the Q factor depends on the angle of the complex pole $p$ from the horizontal axis, $\theta = \arg p$: damping factor $\zeta = \frac{1}{2Q}$, and $\zeta = \cos(\theta)$, and ...
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0answers
48 views

Basic Fourier Transform filtering and LTI frequency response using Matlab

Not sure if this is the right place to ask... I'm new to Matlab for LTI signal processing and wondering if anyone can help with something that I'm sure is meant to be basic. I've spent hours and hours ...
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0answers
47 views

Is it possible from 1 order cascading low pass filters to make a butterworth filter

Today I have heard, that is "impossible" to make low pass butterworth filter from cascading 1 order low pass filters(RC). I am trying to discover is that true, but I can find little to none ...
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1answer
72 views

Pole/Zero Placement for Filter

I'm attempting to design a FIR high pass filter than keeps signals above 200Hz and rejects signals below 60Hz with a sampling frequency of 500 samples/sec. This is my first time attempting this and ...
0
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2answers
44 views

How do I take the real part of this bandpass filter system's output?

I'm stuck on a final step in this problem. Essentially, there are the two systems above, which we'll call System 1 (Fig. 4.26, with ideal lowpass $H(jw)$) and System 2 (with $H_1(jw)$). The ...
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1answer
57 views

Identify the system from input and output

I am using Excel. If I have an input and an output, and I know that a recursive band-pass filter produced the output, how can I can find the coefficients of that filter?
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2answers
30 views

Filter design / Analysis apps

There are a plethora of tools, both commercial and free, which I have found online for designing filters. The ones I have tried (so far) prompt for frequency response, number of steps (for FIR), then ...
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0answers
30 views

Which values do I use to filter a specific frequency with an RLC circuit? [closed]

I have a RLC circuit with transformation $$H(s) = \frac{R}{Ls+\frac{1}{Cs}+R}$$ and I know that by setting $s=j\omega$ I can obtain the frequency response of this system. What I don't understand is ...
0
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1answer
440 views

What is the Roll-Off factor of a Root Raised Cosine Filter?

When designing a root raised cosine filter on Matlab, there is an option to set its "roll-off factor". What does this mean? I have been looking around for a while but I can't seem to find a clear ...
0
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0answers
52 views

FIR filter design using windowing

I am a newbee in DSP. I am using an FIR low pass and high pass filter with rectangular window in C++. I have calculated the filter coefficients using Low pass filter kernel: High pass filter ...
0
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2answers
143 views

FIR vs IIR filter

In my filter design, FIR gives order 14 and IIR gives order 8 or 4. so what are the disadvantages of IIR design?
0
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1answer
54 views

Why bother impluse invariance, bilinear transform?

Now that we can operate in the frequency domain by way of FFT. We can implement ideal lowpass, highpass and bandpass digital filters. then why there many textbooks talk about designing digital ...
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2answers
86 views

multiplications per second for FIR filter

In my filter the fs=300MHz. and no. of coefficients is 31. I have following queries. (1) what will be the number of multiplications per second? (2) can multiplication be done in one clock cycle? (3) ...
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1answer
62 views

FIR filter design

I am designing an FIR filter.my specs are fs=300MHz, Fc=45MHz, Fs=75MHz, passband gain=3dB , stopband attn=>40dB. what parameters I values of a have to provide in firpm for the minimum order filter ...
0
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2answers
56 views

How to pad a windowed sinc filter in the frequency domain

I'm creating windowed sinc filters to apply them to certain signals that I'm dealing with. To design the filters, I'm using the approach described in the book "The Scientist and Engineer's Guide to ...
0
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1answer
48 views

How to periodically estimate states of a LTI if the output is measured irregularly?

How can I periodically estimate the states of a discrete linear time-invariant system in the form $$\dot{\vec{x}}=\textbf{A}\vec{x}+\textbf{B}\vec{u}$$ $$\vec{y}=\textbf{C}\vec{x}+\textbf{D}\vec{u} ...
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1answer
29 views

High Speed Digital Signal Processors [closed]

Can anybody suggest me the highest speed DSPs available in the market now. Also, what would be the best for a filer design application a DSP or an FPGA?
0
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1answer
290 views

group delay of the FIR filter

For an FIR filter, with symmetrical tap values $h[N-1-n]=h[n]$, why is the group delay $\frac{N-1}{2} T$ (where $N$ is the number of taps of the FIR filter and $T$ is the sampling time)? Why is ...
0
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2answers
127 views

direct Frequency domain FIR filtering vs Overlap-add method

I'm trying to do bandpass filtering of a EEG signal samples at 250Hz and benchmarking the following 4 methods of FIR filtering for different filter orders. The length of the signal is 15000 samples. ...